AirHint found the following cheapest return flights from Basel (BSL) to Seoul (ICN) in September 2025 (see full year).

Return flights

30 Sep - 08 Oct	KLM
29 Sep - 12 Oct	KLM
29 Sep - 14 Oct	KLM
22 Sep - 14 Oct	KLM
08 Sep - 24 Sep	Ryanair
15 Sep - 23 Sep	Ryanair
22 Sep - 07 Oct	KLM
29 Sep - 05 Oct	Wizz Air
26 Sep - 09 Oct	easyJet
01 Sep - 15 Sep	Wizz Air
26 Sep - 06 Oct	easyJet
22 Sep - 13 Oct	KLM
22 Sep - 05 Oct	easyJet

Also check the deals for one-way flights from Basel to Seoul in September.

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

Book a cheap hotel in Seoul

Cheap car rent in Seoul

Cheapest return flights from Basel to Seoul in September from 559€

Return flights